Asthma is a chronic disease of the airways that afflicts 12-14 million individuals in the United States and accounts for large numbers of hospitalizations, emergency department visits, and missed school days. Alarming increases in asthma morbidity and mortality have accelerated interest in disparities between levels of increased resistance to breathing and perceived symptoms. For largely unknown reasons, some asthmatics seem more aware of symptoms than others despite similar degrees of airway obstruction. Asthmatic patients unable to detect acute fluctuations in airflow, those who underestimate the severity of airflow obstruction, and those with compromised lung function could be at increased risk for more frequent and severe attacks of asthma. We hypothesize that the control of asthma should improve when there is concordance between levels of airflow obstruction and the perception of increases in the resistance to breathing. We further hypothesize that changes in self-efficacy and changes in symptom perception serve to enable asthma self-management behaviors that result in improved health-related outcomes. Three hundred children with asthma between the ages of 9 and 12 years of age, and at least one parent or other legal guardian, will be enrolled in the project. We propose a 3 x 3 independent groups randomized trial to test the hypothesis that the control of asthma is improved differentially by the combination of self-monitoring experiences and perception training. The three levels of the first between-groups factor (self-monitoring experience) include: no PEFR (symptom diary only);PEFR (and symptom diary);and, PEFR with immediate feedback (and symptom diary). The three levels of the second between-groups factor (perception training) include: no training (resistance breathing only);discrimination training (without performance feedback);and, discrimination training with immediate performance feedback. We predict that demonstrated increases in the concordance between objective and subjective measures of asthma control, enabled by increases in the ability of patients to discriminate between the presence or absence of airflow obstruction, improves symptom management, functional status, and health-related quality of life in children with asthma.